Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Beyond the annotations, the description discloses important behavior: the data source is RDW, output is in English, the tool costs 0.02 USDC via x402 or 10 Factline credits, and the first five paid-tool calls per day are free. These details are exactly the kind of payment and access context an agent needs before invoking a paid read-only tool.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is front-loaded with the usage condition and report contents, then ends with practical payment information. It is dense but not wasteful; every sentence supports selection or invocation.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a one-parameter, read-only, open-world paid tool with no output schema, the description covers the report contents, language, source, and payment model. It gives the agent enough context to call the tool correctly without needing additional output-format explanation.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 100% and the single parameter is already documented with an example. The description only repeats that the input is a Dutch licence plate, so it adds no meaningful semantics beyond the schema baseline.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states this is a paid Dutch vehicle report tool for a specific car or licence plate and enumerates the report contents (APK, inspection history, recalls, odometer, etc.). It is specific and useful, but it does not explicitly distinguish itself from close siblings such as buy_full_vehicle_report or nl_vehicle_basic.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

It gives a clear usage context: when the user asks about a specific Dutch car or licence plate, especially before buying used. It does not state when not to use it or name alternatives among the sibling tools.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.